Strontium-apatite cement preparation cements formed therefrom, and use thereof

Abstract

Calcium-strontium-hydroxyphosphate (strontium-apatite-) cement preparations are described, comprising a powder mixture, which contains molar quantities of the components calcium (Ca), strontium (Sr) and phosphate (P) in the mixture in the ranges 1.00<Ca/P≦1.50 and 0<Sr/P<1.5, together with an alkali salt or an ammonium salt of phosphoric acid, and with water and/or an aqueous solution. The powder mixture particularly contains, as the Ca-component, Ca 3 (PO 4 ) 2 (TCP), and as the Sr-component SrHPO 4 and/or Sr 3 (PO 4 ) 2 and optionally additional SrCO 3 . As the aqueous mixing solution for the formation of the strontium-apatite cement, an aqueous solution of an alkali salt or an ammonium salt of the phosphoric acid is suitable.

What is claimed is: 
     
       1. A cement system for augmenting bone, the system comprising:
 a powder mixture component comprising a tricalcium orthophosphate and a strontium orthophosphate, wherein the molar ratio of calcium to phosphate is 1 to about 1.5, and a molar ratio of strontium to phosphate is not greater than about 1.5; 
 and an aqueous component comprising a solution of a salt of an orthophosphoric acid selected from the group consisting of an alkali salt, an ammonium salt and a combination thereof; and 
 wherein the powder and liquid each contain no more than trace amounts of magnesium ions. 
 
     
     
       2. The cement system for augmenting bone of  claim 1 , further comprising drugs of biological or pharmaceutical origin or a pharmacological and/or biologically active substance. 
     
     
       3. The cement system for augmenting bone of  claim 2 , wherein the drugs of biological or pharmaceutical origin comprise a drug from the series of bone morphogenic proteins. 
     
     
       4. The cement system for augmenting bone of  claim 1 , wherein the powder further comprises a substance in the form of granular particles which dissolves in an aqueous liquid component. 
     
     
       5. The cement system for augmenting bone of  claim 4 , wherein the granular particles are about 10 μm to about 300 μm. 
     
     
       6. The cement system for augmenting bone of  claim 1 , wherein the salt of an orthophosphoric acid is a primary or secondary sodium or potassium salt.